Finally on the road!

dlwilson · January 20, 2017, 7:07pm

It’s been eight years. Three houses. Three girlfriends. One marriage. Three jobs. But it’s running!

In 2009 I bought a 1991 XJS convertible that had been sitting for five years. And I bought a 1996 Chevy Caprice police car. And a bunch of parts from Andrew at Jaguar Specialties. I figured it would take about six weeks to do the conversion. Ha!

It’s been a long, long, long road, but a couple weeks ago I was able to drive around the neighborhood. The only big issue I have left is the charging system (which isn’t) but I have a pretty good idea what is wrong, and am hope to get it fixed tonight.

LT1 engine and PCM, 4L60E transmission
Sanderson shorty headers, ceramic coated
true dual exhaust with X-crossover, welded by me. with only the resonators it is surprisingly quiet
converted from crazy ABS brakes to standard power brakes from 1988 XJS
all new calipers and hoses front and rear
all new bushings and springs in front suspension
new trailing arm bushings and rear axle mounts
all new Boge shocks (traded for the removed ABS pump)
PSI wiring harness (I hacked the original harness so many times that I no longer trusted it)
4th gen Camaro radiator and fans
complete AC in place, ready to be evacuated, tested, and used
custom bracket to mount PCM in fender behind front passenger wheel
fuses and relays mounted in box on passenger firewall inside cabin

More than once I got to be so sick of the project that I swore I would sell it if I could only get it running and driving. But now it is a lot of fun to drive, and I’m looking forward to making it a reliable road vehicle.

Cadjag · January 21, 2017, 1:52pm

My hearty congratulations. That is a beautiful car. The Caprice package is a great fit. Dealing with the “no charge” might well be the easiest task that you have had to do in making the conversion. Big 140 AMP Delco up top and front. Access, durn near too easy. The Serpenpentine must be there or you would not have taken the Victory lap!!! Only two wires to deal with. And, I’m sure you have a path for them.

I suspect your car is OBD II. Lots of data with the right scan tool.

Are you in CA or a state that requires a special inspection. That can be a pain. Don’t ask.

Well worth the travail, huh!!!
As your photo skills are apparent, how about some under the bonnet shots.

Carl

Motley · January 22, 2017, 8:34am

Congratulations! Looks great.

I second the call for pics

dlwilson · January 23, 2017, 5:56pm

Here’s some underhood photos. I’m still chasing the no charge alternator, but PSI tech support has been very responsive.

Yes, the car is OBD-II, and I have the diag port under the passenger side dash. That’s been really helpful throughout. No, we don’t have emissions in Florida. I removed the cats and the rear O2 sensors, as well as all of the EGR equipment. I still need to get the PCM reprogrammed to remove all of that stuff, but I doubt it will change how the engine runs.

Passenger side photo. There are still a few wires to tidy up on this side. I’m waiting until I get the tach and the water temperature gauge working, as well as running the wires to the compressor and A/C low pressure switch. That’s the original accumulator and compressor on there for now; I have new replacements on the shelf for when it’s time to get the AC working. I had to weld up a bracket to hold the PS reservoir to the alternator bracket.

Drivers side. You can see the brake booster I put in from a 1988. I had to piece together the whole brake system from eBay and junkyards. I didn’t trust the ABS, didn’t want the repair bill when it failed, and did want the space it took up under the hood. There’s still some original Jaguar wiring and relays to come out on this side also. That’s a Dorman coolant overflow bottle. I couldn’t find anything else that fit as well. Spectre intake. GM quick disconnect fittings from Dorman, crimped onto the fuel lines, which are then hose clamped onto the barbed Jaguar fuel fittings. The fuel pressure gauge is still on there from when I was diagnosing low fuel pressure. Do you find that the original fuel pump provides the 43.5 psi that the LT1 requires? There are Nomex spark plug boots on all of the plugs to prevent the wires from melting on the headers.

Cadjag · January 23, 2017, 9:08pm

Nice work. I can’t spot the MAF in the intake ? Nor the bleed hose for the OPTILITE? Not to say they are not present

My car’s over flow is the Jag unit behind the left outboard headlight. So far, just fine.

Yes, the Jaguar pump has the capacity. Mine has done just fine.

I’m not sure you need a reprogram? A scan will indicate fails on he missing EGR, air pump, but so?
As it started, your PCM had no VATS to disable.

Carl

dlwilson · January 23, 2017, 11:34pm

The MAF is just after the conical air filter. And I believe the Optispark vent hose runs to the intake elbow, which is an aftermarket piece of cast aluminum. I used a little VATS box which sends the correct signal to the PCM to defeat VATS.

I currently have the Jaguar fuel pump installed, but the fuel gauge only shows 30 psi at the rail. I’m waiting on an eBay auction for a Walbro pump which goes up to 60 psi. I have an adjustable fuel pressure regulator which will drop it down to 43.5 psi.

The reprogram is only to stop the PCM from throwing codes for missing sensors like: O2 sensors, transmission temp sensor, knock sensor, crank position sensor, and EGR equipment. I would also like a mail order tune to adjust for the headers and free-flow intake.

I have a tach converter which takes the 8 cylinder tach signal from the PCM and converts it to a 12 cylinder signal which should work with the Jaguar tach, but the tach seems to be stuck. If I tap on it, it will move to a new position, but it won’t sweep back and forth. I also tied the LT1 coolant temperature sensor into the Jaguar temperature gauge, but don’t get any readings on it.

rtloft · January 24, 2017, 3:14am

Your conversion looks great! I had a good chuckle at your opening statement at the top of this thread. I showed the wife (yes she is still my wife) and she could identify (only 2 houses and no mention of girlfriends ) For water temp, you’ll need to install the Jag temp sensor into the threaded port in one of the heads and wire it directly to the gauge. The LT1 PCM has a sensor in one of the heads but there is a plug (with a square drive hole) in the head on the other side. Remove the plug and install the Jag sensor (with adapter since the threads are different). WRT the fuel pump, the original Bosch pumps work great. It should have no problem supplying flow at the correct pressure. Your original pump may be dying or your regulator may not be working correctly. Also, check that the fuel pick-up strainer in the tank (if similar to the XJ6) is not clogged or plugged up. Again, nice looking install. Enjoy!

dlwilson · January 30, 2017, 4:04pm

Thanks for the kind words. I finally took the advice of PSI and put in a genuine remanufactured AC Delco alternator, and all my charging problems went away.

I won my eBay auction for a Walbro fuel pump, and am waiting on shipping. I think this will get my fuel pressure up to 43.5 psi at the rail, and maybe a little more power. https://www.summitracing.com/parts/vpn-gsl392bx I did clean out the sump tank and put a new strainer on the fuel pick-up.

It would be nice to have the coolant temperature gauge working as I have been using my tablet connected to the ODB-II dongle to get engine temperature… Is this the correct sensor: https://www.amazon.com/Jaguar-Vanden-Coolant-Temperature-DAC002583/dp/B009PQB5NQ? And the interweb seems to say that sensor has 1/8" NPT pipe thread, while the LT1 cylinder head has 1/4" NPSF thread. So a 1/8" NTP to 1/4" NTP adapter should work.

The tachometer doesn’t work either. It acts like it is stuck. If I tap on it, it will jump to the correct engine rpm, but it won’t move after that. I don’t know whether to try to clean it, or just replace it.

I noticed a couple days ago that the poly bushings I put into the upper and lower control arms are crumbling already. Well, I did put them in eight years ago, but they have less than 10 miles on them. I can hear the bushings creaking and rattling when I drive. So the arms have to come off the replace the bushings.

boboli · February 13, 2017, 9:32am

Awesome job. I did nearly the exact same thing to my 89 XJS convertible. I agree on your abs removal. My car sat for several years and the reservoir cracked in the sun, contaminating the brake fluid. I tried and tried to save the abs, but after much frustration, time, and money I did what you did and retrofit a vacuum assist brake system.
Maybe I missed it, but why do you think the fuel pump is the cause of low fuel pressure? Were the Jaguar pumps limited on their pressure? Most fuel injection pumps can run in the 60-100 psi range. The regulator brings the pressure down to the psi that the system requires. Sure the pump can be going bad and losing its ability to make enough psi, but I would think something else is causing the problem. have you tried blocking the return line after the regulator and seeing if the psi spikes?

dlwilson · February 13, 2017, 8:19pm

It was interesting piecing the vacuum assist brake system together. I bought the booster and some lines off eBay, but eventually I was lucky to find an XJS being parted out locally, and I got the rest of the hard brake lines off it.

I suspect the fuel pump, but am not positive. I tested the fuel pressure before the rail, and it spiked the fuel pressure meter. When I test after the fuel pressure regulator at the rail I get the lower pressure. I put on an adjustable FPR, and when I turned the fuel pressure up to 43.5 the pump began to whine loudly enough to hear when driving. My new Walbro pump still shows about 35 psi at the rail, so I need to put the adjustable FPR back on, and see if the Walbro whines as well.

I am currently working on replacing the crumbled front suspension control arm bushings. I can barely remember how I did this eight years ago. I got out my homemade XJS front spring compressor, and am trying to figure out how to use it.

Cadjag · February 14, 2017, 3:38pm

Progress often includes stumbles along the way. One cause is that memory thing. Been there. At last resolved!!!

Pump whine. Are the line/s fro m tank/s to pump free and clear? Is the delivery line free and clear?
Same for the return.

Does the pump whine when not under load? Is it free and clear?

Is it the way the pump is mounted, stiff or isolated that transmits normal noise?

Although, my ears are not that good, even when I wear my aids, I hear no pump whine.

Are you sure, the noise you hear is the pump?

Are you sure that is a spring compressor? Looks too wimpy to contain that kind of tension. Careful, folks get badly hurt messing around there.

Carl

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dlwilson · March 20, 2017, 2:10pm

An update! I got the front control arm bushings replaced. Not much difference in the ride, but no more clunking from the front end. My home made spring compressor is made of 3/4" threaded rod, so it is up to the task. This time I used 5/16" threaded rod in each of the four spring pan bolt holes on the lower control arm as guides, so the pad would ride right up the guides onto the lower control arm.

I installed the above referenced temperature sensor, wired it in, and now my temperature gauge works. I filled the tank halfway, and confirmed that the fuel gauge works. The amp gauge works, the oil pressure gauge works, and the speedo obviously works because on these cars it takes its signal directly from the rear axle. The only thing not working is the tach, so I’ll probably just buy a used one on eBay and replace, and see if that fixes it.

I have put about 75 miles on the car around town, all with the top down, and it is much fun to drive. I haven’t had it over 50 mph. After 100 miles I will check and tighten all the nuts and bolts, and then venture out on the highway.

Remaining work:

Evacuate and charge the AC, and connect heater lines and valve. I have a new compressor and accumulator ready to go in. I need to figure out the vacuum connection to operate the vent doors and the heater valve. Hopefully there are no leaks in the AC system. I have another month or two until it gets hot here.

Fix the pump or motor for the top. All I know so far is that when I press the button I hear the motor humming, but get no movement. Also there is oil all over the pump/motor. And I would like the rear windows to go up and down as well.

Tires and alignment. I am running used tires on it for now. I’m torn between going to 17" wheels or staying original. The car tracks straight, but when I get new tires I think I need an alignment.

Paint. The car has only a quarter-sized rust spot, but the clear coat is peeling and the hood and trunk lid paint are worn. I would like to try the poly dip spray, and keep it in the original green, but with the matte finish you get with dip.

Details: radio, seats, interior wood strips on the door. And that should do it!